Is my alternator failing?

Need some help with a technical problem - ask away and let's see if we can all help.

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Sam
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Is my alternator failing?

Post by Sam »

This isn’t on a Porsche.

It’s on the stupid sort of car that looks like it’ll need the whole engine, gearbox and subframe dropping to remove the alternator.

Battery is new, reads ~12.x with the engine off.

At idle reads ~14.x.

When revved reads ~12-13.x

When lights are on drops to ~12.x at idle.

It’s clearly charging a bit, but after a 2 hour drive the charge light started flickering on and off and 15 mins later it died.
964 C2 Targa. 205 1.6 GTi. Testarossa. Fisher Fury Fireblade. Motorhome. Motorbikes. Scooters. Pushbikes. Threadbare Saucony Peregrines. Dog. Human relations and friends. 97.5%-built house.
SeanP
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Re: Is my alternator failing?

Post by SeanP »

Sounds like the regulator is failing to me.
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misteralz
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Re: Is my alternator failing?

Post by misteralz »

What Sean says. I'd chance a new regulator pack first. For the sake of 25 quid or so and less disassembly it's worth a shot.
Lightweight_911
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Re: Is my alternator failing?

Post by Lightweight_911 »

.

If it's the car I think it is (Testarossa), the VR is integral with the alternator &, as Sam says is not particularly simple to remove - mid engine layout - (although I'm fairly sure it doesn't involve engine removal).

An obvious question but have you checked the belt tension (bearing in mind the awkward adjustment access) ?

.
Andy

“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
Sam
Nurse, I think I need some assistance
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Re: Is my alternator failing?

Post by Sam »

Thanks guys.

Yes, the regulator is part of the alternator but looking again I reckon I can remove a grill and panel and get it out without dropping everything. Hopefully.

I did check the belt!
964 C2 Targa. 205 1.6 GTi. Testarossa. Fisher Fury Fireblade. Motorhome. Motorbikes. Scooters. Pushbikes. Threadbare Saucony Peregrines. Dog. Human relations and friends. 97.5%-built house.
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MikeB
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Re: Is my alternator failing?

Post by MikeB »

Check that your main battery lead to the starter motor is tight, I had a similar issue and that’s what it was. The starter was working fine so I didn’t think that was the issue
Cheers

Mike

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